The Baseline Engaged Segment (60 Days)
When your email deliverability is completely in the trash can, blasting your full list will only dig the hole deeper. Across the brands we work with at In-box, where we have driven over $5.8 million in email and SMS revenue, the first lever we pull is aggressive engagement filtering.
You need to start with a tight baseline. I build a 60-day engaged segment inside Klaviyo to capture profiles actively interacting with the brand. That means someone who has opened an email at least once in the last 60 days, clicked an email in the last 60 days, been active on site in the last 60 days, or placed an order in the last 90 days (using OR logic between each condition).
Finally, we add an AND condition requiring that the profile can receive marketing. This 60-day window is intentionally strict. When your open rates are depressed and your emails are landing in the spam folder, restricting your volume to genuinely active recipients is the only way to signal inbox providers that people actually want your mail.
Why New Subscribers Get a Shorter Window
Alongside engagement activity, we include recently subscribed profiles so that new leads receive campaigns. However, I never match the signup condition to the 60-day window. I restrict it to people who subscribed to the list at least once in the last 30 days.
Here is the thing: if someone joined your list 45 days ago and has not opened a single email, clicked a link, or visited your site since, they are not engaged. Giving non-responders 60 days of campaign sends simply because they entered their email once is a fast way to hurt your sender reputation.
Keep that signup inclusion window at 30 days. If they do not interact with your welcome sequence or initial campaigns within that first month, they do not belong in your regular broadcast sends.
Expanding to 90 Days (and Why 150 Is a Trap)
Once you see healthy metrics on your 60-day sends, you can start expanding. I look for open rates consistently hitting 50% to 60% with solid 2% click rates before widening the audience.
When those benchmarks hold, clone your segment and expand the engagement conditions to 90 days. If deliverability remains steady, you can test a 120-day segment. If your numbers drop off or open rates plummet after expanding, drop it straight back to 60 days. In severe cases, 60 days might still be too broad, meaning you should pull back to a 30-day engaged segment.
One thing I avoid is sending to a 150-day segment. In almost every Klaviyo account I audit, jumping from 120 to 150 days only adds roughly 600 to 1,000 unengaged contacts. Risking your inbox placement for a fraction of a percent in additional reach is not worth it.
Building Your Campaign Exclusion Segments
Fixing deliverability is as much about who you exclude as who you include. There are two essential exclusion segments you need to attach to every single campaign.
The first is a recent bounce segment. Create a dynamic segment for anyone who has bounced at least once in the last 30 days. Typos on signup forms mean the welcome series often incurs the highest bounce volume. Filtering these profiles out protects your sender score while Klaviyo processes suppressions.
The second mandatory exclusion is anyone currently going through your welcome flow. Bombarding a brand new subscriber with three weekly campaigns while they are also receiving onboarding emails leads to quick fatigue. That creates high spam complaints and instant unsubscribes.
Timing the Welcome Series Exclusion
To exclude welcome flow recipients cleanly, build a segment based on when they subscribed. Calculate the total duration of your welcome series and add a small buffer window.
For example, if the final email of your welcome sequence goes out on day seven, set your exclusion rule to people who subscribed in the last nine days. That gives the subscriber a two-day break after completing the automated flow before they enter your standard campaign rotation.
Some brands worry about excluding people who subscribe during checkout and skip the standard popup. However, those customers should already be receiving your post-purchase sequence. Giving them breathing room across all channels keeps engagement high and unsubscribes low.
Putting the Campaign Send Together
When you schedule your campaign in Klaviyo, select your engaged segment as the main recipient list. Then, add both the recent bounce segment and the welcome flow segment into the exclusion box.
In a standard account, this process will often reduce your total recipient count significantly. In one recent setup, our starting segment dropped from 24,000 down to 21,518 contacts once exclusions were applied. Trimming thousands of unengaged contacts might feel counterintuitive, but sending fewer emails to better people delivers higher revenue every time.
Final Thoughts
Deliverability issues do not resolve themselves with clever subject lines or redesigned templates. If your emails are landing in spam, tighten your campaign audience to a strict 60-day window, suppress recent bounces, and protect subscribers in your automated flows. Once inbox providers see strong engagement, you can safely scale your reach again.
Fix Your Deliverability
If your open rates are declining or your campaigns are missing the primary inbox, we can audit your account setup and segmentation. Learn more about our campaign management on our email campaigns page.
